136 THE PROBLEM OF EVOLUTION 



blood must not, without further consideration, 

 be regarded as proving Hood-relationship in 

 the sense of having a common origin. Apart 

 from his experiments on the reaction of blood, 

 Dr. Friedenthal himself is as much a ' dilet- 

 tante scientist,' i.e. a non-specialist on the 

 subject of the origin of man, as I am. 



Friedenthal expressed a wish to distinguish clearly 

 the realms of the natural and intellectual sciences 

 respectively. He declared the former to be con- 

 cerned with processes of motion, and the latter 

 with conceptions and ideals. In dealing with the 

 natural sciences, he said, the scientist was free and 

 unfettered, and could establish his results regardless 

 of historical evolution and of dogmas. But in 

 dealing with conceptions or ideals, there would 

 always be warfare, for here there was an absence 

 of the proofs which are a preliminary condition for 

 the attainment of definite results. Consequently, 

 in the realms of ideals, the attainment of results 

 did not depend upon so-called proofs, which no one 

 could fail to accept, but rather upon personal 

 feelings. As to his own attempts to prove community 

 of origin from blood-relationship, this was a matter 

 in which there was no logical evidence acting 

 irresistibly upon each individual. The speaker 

 considered that we could not bring forward such 

 conclusive evidence of origin, even in the case of a 

 child of some particular married couple. ' The 



